Our acid-free White Linen Canvas matboards are 4-ply and feature a white core. With an overall size of 30x40, these mats with Oval openings fit perfectly into 30x40 frames and are bevel cut to showcase your 27x36 photos. Actual mat opening size is 26.5x35.5 inches so that it may safely and securely house your 27x36 photo, artwork, needlepoint, sign, etc. This pack includes 1 Single Matboard Show Kit With Acid Free Backing & Clear Bag. Proudly made in the USA by Country Art House!